20MnSiNb钢高温塑性及其与Nb(C,N)析出的关系  

Hot Ductility of 20MnSiNb Steel and Its Relationship With Nb(C,N) Precipitates

作　　者：宋海武[1] 艾星辉[2] 齐长发[1] 臧振东[1] 

机构地区：[1]唐山钢铁股份有限公司技术中心,河北唐山063016 [2]唐山科技职业技术学院冶金系,河北唐山063001

出　　处：《热加工工艺》2007年第20期27-31,共5页Hot Working Technology

摘　　要：应用Gleeble-3500热/力模拟试验机研究了不同奥氏体化温度及不同应变速率下20MnSiNb钢的高温塑性,发现降低奥氏体化温度及增加应变速率均可使第III脆性区的塑性好转。当奥氏体化温度为1 350℃、应变速率为0.001 s-1、拉伸温度低于1 025℃时,塑性急剧下降。用扫描电镜、透射电镜及光镜分别观察了断口形貌、析出物以及断口金相组织,确定了断裂模式,分析了脆化原因。同时指出了试验钢在实际生产条件下适宜的铸坯矫直温度及轧制过程中铸坯开裂的可能性。The hot ductility of 20MnSiNb steel at different strain rate and different heating temperature was studied using Gleeble-3500 thermal-mechanical simulator. It＇s found that the ductility in embrittlement region Ⅲ improves as the strain rate increases or heating temperature decreases. When heating temperature is 1 350℃, strain rate is0.001s^-1 and tensile temperature is below 1 025℃, the hot ductility decreases rapidly. The fractographs, precipitates and micrographs were observed by SEM, TEM and optical microscope. The fracture mode was made sure. The reason of embrittlement was analyzed. The appropriate temperature of continuous cast slab turning to flat and the cracking possibility during rolling manufacture were indicated.

关 键 词：含铌钢 连铸坯 热塑性 应变速率 

分 类 号：TG142.41[一般工业技术—材料科学与工程]